Strange nullReferenceError when dealing with Hashtables and Photon

Hey guys,

This one is a real mind bender, and i've been struggling with this for the past few days.

To keep this short, I'm building the foundations of a multiplayer game using Photon within Unity. Photon allows you to apply custom properties to certain server objects (such as a player or a "room") by passing a hashtable to the SetCustomProperties() method, which seems like a very useful tool. However this problem is disallowing me the ability to use this.

So, in order to make things more rigid, i'm trying to use objects instead of hashtables, and i've created a simple class to easily convert the object to a hashtable, and convert the hashtable to the object. Here is the basic class that for setting and getting the custom room properties:

 using UnityEngine;
 using System.Collections;
 
 public class PhotonRoomInformation {
     
     public string type = ""; //this will either be "quick" or "custom"
     public string status = ""; //this will be either "game" or "lobby"
     public int maxPlayers = 0;
     public int numPlayers = 0;
     
     public PhotonRoomInformation()
     {
         this.type = "";
         this.status = "";
         this.maxPlayers = 0;
         this.numPlayers = 0;
     }
     
     //get hashatable from the manually set parameters
     public Hashtable getHashTable()
     {
         Hashtable ht = new Hashtable();
         ht.Add("type",type);
         ht.Add("status",status);
         ht.Add("maxPlayers",maxPlayers);
         ht.Add("numPlayers",numPlayers);
         
         return ht;
     }
     
     //set the properties from a passed hashtable
     public void setProperties(Hashtable ht)
     {
         this.type = (string)ht["type"];
         this.status = (string)ht["status"];
         this.maxPlayers = (int)ht["maxPlayers"];
         this.numPlayers = (int)ht["numPlayers"];
     }
 }

Now, using the getHashTable() method works fine. I have tested this thoroughly by seeing what the server recieves and sends back. Everything matches up.

However, when I try to use the setProperties() method, by passing the customProperties hashtable of the room to the method, I get a null reference error.

Here is the part of code where I am trying to perform this method:

     //when the rooms properties have updated, check that the room is full. If so, we're ready to load the game
     void OnPhotonCustomRoomPropertiesChanged()
     {
         PhotonRoomInformation pri = new PhotonRoomInformation();
         pri.setProperties(PhotonNetwork.room.customProperties);
         
         //if the status is in game, load the level
         if(pri.status == "game")
         {
             print ("loading level!");
             PhotonNetwork.LoadLevel(quickMatchScene);
         }
     }

Which gives me this exact error: NullReferenceException: Object reference not set to an instance of an object PhotonRoomInformation.setProperties (System.Collections.Hashtable ht) (at Assets/Standard Assets/Scripts/Utilities/PhotonRoomInformation.cs:36) quickmatchMenu.OnPhotonCustomRoomPropertiesChanged () (at Assets/Standard Assets/Scripts/Menus/quickmatchMenu.cs:186)

Line 36 of PhotonRoomInformation.cs (the class shown in this post) is this:

this.maxPlayers = (int)ht["maxPlayers"];

Line 186 of quickmatchMenu.cs is part of the extract shown above:

pri.setProperties(PhotonNetwork.room.customProperties);

Any help would be greatly appreciated.

 foreach(var key in ht.$$anonymous$$eys)
 {
     Debug.Log(key + ": " + ht[key]);
 }

 this.maxPlayers = (int)ht["maxPlayers"];

 var tmp1 = ht["maxPlayers"];
 Debug.Log(tmp1);
 Debug.Log(tmp1.GetType());
 var tmp2 = (int)tmp1;
 Debug.Log(tmp2);
 this.maxPlayers = tmp2;